Alex Boone prepared to replace Joe Staley at left tackle

The typically loquacious Joe Staley was a man of few words following the 49ers 23-13 win over the Rams and who could blame him?

The team’s Pro Bowl left tackle exited in the first half with a right knee injury, and before he even hit the locker room, Staley was declared out for the rest of the game.

“I am not going to talk about it,” Staley said upon leaving the locker room Sunday evening. “We will find out.”

It means Staley will likely have further examinations on Monday to determine the extent of the injury. The Sacramento Bee and Comcast sports Bay Area both quoted a team source saying Staley had sprained the MCL ligament in his knee.

A team is obviously weakened when they lose a top flight left tackle. But you would not have known that Sunday.

Alex Boone, the team’s starting right guard, shifted to left tackle and then proceeded to shut out Rams pass rusher Robert Quinn, who entered the game with 13 sacks.

“Just like riding a bike, it’s like going back home,” said Boone, who spent eight years at tackle, before shifting two years ago to guard.

Boone has always known he could shift back to tackle if one of the starters got hurt, but he only lightly prepares for that possibly. He’s still learning to play guard, so he devotes all his time, except for maybe four practice snaps a week, to guard.

When Boone shifted out to tackle, he had not studied Quinn on film at all. Nevertheless, Boone tired quickly of talking about his own performance and was more interested in talking about second-year player Joe Looney, who replaced him at right guard.

“He came off the bench and just kicking some ass, can’t be more proud of a guy than that,” Boone said of Looney. “I know he’s going to be ready this week.”